Engine including valve geometry relative to bore size

ABSTRACT

An engine assembly may include an engine block defining a cylinder bore, a cylinder head coupled to the engine block, a first intake valve, a fuel injector in communication with the cylinder bore and a spark plug in communication with the cylinder bore. The cylinder bore may define a first diameter. The cylinder head may define a first intake port and a first exhaust port in communication with the cylinder bore. The first intake valve may be located in the first intake port and may define a second diameter at least 35 percent of the first diameter. The fuel injector and the spark plug may be located centrally relative to the cylinder bore.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 61/345,369, filed on May 17, 2010. The entire disclosure of the above application is incorporated herein by reference.

FIELD

The present disclosure relates to engine intake and exhaust valve and port geometry, and more specifically to intake and exhaust valve and port geometry defined by cylinder bore size.

BACKGROUND

This section provides background information related to the present disclosure which is not necessarily prior art.

Internal combustion engines may combust a mixture of air and fuel in cylinders and thereby produce drive torque. Intake ports may provide air flow to the combustion chamber for combustion. The products of combustion may exit the combustion chamber via exhaust ports. As engines become increasing smaller, accommodating appropriate valve and port sizes becomes more difficult.

SUMMARY

An engine assembly may include an engine block defining a cylinder bore, a cylinder head coupled to the engine block, a first intake valve, a fuel injector in communication with the cylinder bore and a spark plug in communication with the cylinder bore. The cylinder bore may define a first diameter. The cylinder head may define a first intake port and a first exhaust port in communication with the cylinder bore. The first intake valve may be located in the first intake port and may define a second diameter at least 35 percent of the first diameter. The fuel injector and the spark plug may be located centrally relative to the cylinder bore.

The first diameter may be less than 80 millimeters. The engine assembly may additionally include a first exhaust valve located in the first exhaust port and defining a third diameter at least 30 percent of the first diameter. More specifically, the second diameter may be at least 37 percent of the first diameter and the third diameter may be at least 32 percent of the first diameter.

The cylinder head may additionally define a second intake port and a second exhaust port in communication with the cylinder bore. The first and second intake ports may be located on a first radial half of the cylinder bore and the first and second exhaust ports may be located on a second radial half of the cylinder bore opposite the first radial half.

A first line extending radially through a center of the cylinder bore and a center of the first intake valve extends at an angle of between 40 degrees and 44 degrees relative to a line extending radially across the cylinder bore defining the first radial half and the second radial half when the first intake valve is in a seated position. A second line extending radially through the center of the cylinder bore and a center of the first exhaust valve extends at an angle of between 39 degrees and 43 degrees relative to the line extending radially across the cylinder bore defining the first radial half and the second radial half when the first exhaust valve is in a seated position.

The engine assembly may include a second intake valve located in the second intake port and defining a fourth diameter at least 37 percent of the first diameter and a second exhaust valve located in the second exhaust port and defining a fifth diameter at least 32 percent of the first diameter.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure in any way.

FIG. 1 is a schematic illustration of an engine assembly according to the present disclosure; and

FIG. 2 is a schematic fragmentary top plan view of the engine assembly of FIG. 1 illustrating intake and exhaust ports relative to the cylinder bore and fuel spray of the engine assembly of FIG. 1.

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Examples of the present disclosure will now be described more fully with reference to the accompanying drawings. The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

When an element or layer is referred to as being “on,” “engaged to,” “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

An engine assembly 10 is schematically illustrated in FIGS. 1 and 2 and may include an engine structure 12, first and second intake valves 14, 15, first and second exhaust valves 16, 17, a piston 18, a spark plug 20 and a fuel injector 22. The engine structure 12 may include an engine block 24 defining a cylinder bore 28 and a cylinder head 26 coupled to the engine block 24. The piston 18 may be disposed in the cylinder bore 28. The engine block 24, the cylinder head 26 and the piston 18 may cooperate to define a combustion chamber 30.

The first and second intake valves 14, 15 may each extend at an intake valve angle (α_(I)) relative to a sidewall of the cylinder bore 28. The intake valve angle (α_(I)) may be between 19 degrees and 21 degrees. In the present non-limiting example, the intake valve angle (α_(I)) is approximately 20 degrees. The first and second exhaust valves 16, 17 may each extend at an exhaust valve angle (α_(E)) relative to the sidewall of the cylinder bore 28. The exhaust valve angle (α_(E)) may be between 17.5 degrees and 19.5 degrees. In the present non-limiting example, the exhaust valve angle is approximately 18.5 degrees.

The cylinder head 26 may define intake and exhaust passages 32, 34 in communication with the combustion chamber 30. In the present non-limiting example, the intake passages 32 may define a first intake port 36 in communication with the cylinder bore 28 at the combustion chamber 30 and a second intake port 37 in communication with the cylinder bore 28 at the combustion chamber 30. The first intake valve 14 may be located in the first intake port 36 and the second intake valve 15 may be located in the second intake port 37.

The exhaust passages 34 may define a first exhaust port 38 in communication with the cylinder bore 28 at the combustion chamber 30 and a second exhaust port 39 in communication with the cylinder bore 28 at the combustion chamber 30. The first exhaust valve 16 may be located in the first exhaust port 38 and the second exhaust valve 17 may be located in the second exhaust port 39. It is understood that the present teachings apply to any number of piston-cylinder arrangements and a variety of engine configurations including, but not limited to, V-engines, inline engines, and horizontally opposed engines, as well as both overhead cam and cam-in-block configurations.

The spark plug 20 may be in communication with the cylinder bore 28 and located centrally relative to the cylinder bore 28 and the fuel injector 22 may be in communication with the cylinder bore 28 and located centrally relative to the cylinder bore 28. The spark plug 20 and the fuel injector 22 may each be located in the cylinder head 26 and may be in direct communication with the combustion chamber 30. In the present non-limiting example, the spark plug 20 and the fuel injector 22 may be centrally located in the combustion chamber 30 relative to an outer radial perimeter defined by the cylinder bore 28, forming a central direct injection configuration. The spark plug 20 and the fuel injector 22 may each be radially offset from a center (C_(B)) of the cylinder bore 28 in directions opposite one another.

With reference to FIG. 2, the location and size of the first and second intake valves 14, 15 and the first and second exhaust valves 16, 17 may be defined as a function of the cylinder bore 28. As seen in FIG. 1 and as discussed above, the first and second intake valves 14, 15 and the first and second exhaust valves 16, 17 may be disposed at an angle relative to the cylinder bore 28. However, for simplicity FIG. 2 illustrates the cross-sections of the first and second intake valves 14, 15 and the first and second exhaust valves 16, 17 being perpendicular to the cylinder bore 28 to better illustrate the relation between the first and second intake valves 14, 15 and the first and second exhaust valves 16, 17 and the cylinder bore 28.

A first axis (A1) may extend through the center (C_(B)) of the cylinder bore 28 between the first intake port 36 and the second intake port 37 and between the first exhaust port 38 and the second exhaust port 39. A second axis (A2) may extend through the center (C_(B)) of the cylinder bore 28 perpendicular to the first axis (A1). The first and second intake ports 36, 37 and the first and second intake valves 14, 15 may be symmetric about the first axis (A1). The first and second exhaust ports 38, 39 and the first and second exhaust valves 16, 17 may be symmetric about the first axis (A1). Therefore, the first intake valve 14, the first intake port 36, the first exhaust valve 16, and the first exhaust port 38 will be discussed with the understanding that the description applies equally to the second intake valve 15, the second intake port 37, the second exhaust valve 17 and the second exhaust port 39.

The first and second intake valves 14, 15 and the first and second intake ports 36, 37 may be located on a first radial half of the cylinder bore 28. The first and second exhaust valves 16, 17 and the first and second exhaust ports 38, 39 may be located on a second radial half of the cylinder bore 28 opposite the first radial half. The spark plug 20 and the fuel injector 22 may be located between the first and second radial halves. The second axis (A2) may define a line extending radially across the cylinder bore 28 and defining the first radial half and the second radial half.

The cylinder bore 28 may define a first diameter (D_(B)), the first intake valve 14 may define a second diameter (D_(I1)) and the first exhaust valve 16 may define a third diameter (D_(E1)). The spark plug 20 and the fuel injector 22 may be located centrally (radially) within the first intake port 36 and the first exhaust port 38. The first diameter (D_(B)) of the cylinder bore 28 may be less than 80 millimeters, and more specifically less than 75 millimeters. In the present non-limiting example, the first diameter is approximately 74 millimeters.

By way of non-limiting example, the second diameter (D_(I1)) may be at least 35 percent of the first diameter (D_(B)) and the third diameter (D_(E1)) may be at least 30 percent of the first diameter (D_(B)). More specifically, the second diameter (D_(I1)) may be at least 37 percent of the first diameter (D_(B)) and the third diameter (D_(E1)) may be at least 32 percent of the first diameter (D_(B)).

As discussed above, the second intake valve 15 may be similar to the first intake valve 14 and the second exhaust valve 17 may be similar to the first exhaust valve 16. Therefore, the second intake valve 15 may define a fourth diameter (D_(I2)) at least 35 percent of the first diameter (D_(B)) and the second exhaust valve 17 may define a fifth diameter (D_(E2)) at least 30 percent of the first diameter (D_(B)). More specifically, the fourth diameter (D_(I2)) may be at least 37 percent of the first diameter (D_(B)) and the fifth diameter (D_(E2)) may be at least 32 percent of the first diameter (D_(B)). In the present non-limiting example, the second and fourth diameters (D_(I1), D_(I2)) are approximately 38 percent of the first diameter (D_(B)), and the third and fifth diameters (D_(E1),D_(E2)) are approximately 32 percent of the first diameter (D_(B)).

The location of the center of the first intake valve 14 and the center of the first exhaust valve 16 may each be defined as a function of the cylinder bore 28 as well. A first line (L_(I)) extending radially through the center (C_(B)) of the cylinder bore 28 and the center (C_(I)) of the first intake valve 14 may extend at a first angle (θ_(I)) relative to the second axis (A2) when the first intake valve 14 is in a seated position (closed position). A second line (L_(E)) extending radially through the center (C_(B)) of the cylinder bore 28 and the center (C_(E)) of the first exhaust valve 16 may extend at a second angle (θ_(E)) relative to the second axis (A2) when the first exhaust valve 16 is in a seated position (closed position). By way of non-limiting example, the first angle (θ_(I)) may be between 40 degrees and 44 degrees and the second angle (θ_(E)) may be between 39 degrees and 43 degrees. In the present non-limiting example, the first intake valve 14 and the first exhaust valve 16 may be located such that the first angle (θ_(E)) is approximately 42 degrees and the second angle (θ_(E)) is approximately 41 degrees.

A first radial distance (D_(LI)) defined along the first line (L_(I)) between the center (C_(B)) of the cylinder bore 28 and a radially innermost portion of the first intake valve 14 may be less than 25 millimeters when the first intake valve 14 is in the seated position. A second radial distance (D_(LE)) defined along the second line (L_(E)) between the center (C_(B)) of the cylinder bore 28 and a radially innermost portion of the first exhaust valve 16 may be less than 27 millimeters when the first exhaust valve 16 is in the seated position. In the present non-limiting example, the first radial distance (D_(LI)) is approximately 23 millimeters and the second radial distance (D_(LE)) is approximately 26 millimeters. 

1. An engine assembly comprising: an engine block defining a cylinder bore defining a first diameter; a cylinder head coupled to the engine block and defining a first intake port and a first exhaust port in communication with the cylinder bore; a first intake valve located in the first intake port and defining a second diameter at least 35 percent of the first diameter; a fuel injector in communication with the cylinder bore and located centrally relative to the cylinder bore; and a spark plug in communication with the cylinder bore and located centrally relative to the cylinder bore.
 2. The engine assembly of claim 1, further comprising a first exhaust valve located in the first exhaust port and defining a third diameter at least 30 percent of the first diameter.
 3. The engine assembly of claim 2, further comprising a second intake valve and a second exhaust valve, the cylinder head defining a second intake port and a second exhaust port, the second intake valve being located in the second intake port and defining a fourth diameter at least 35 percent of the first diameter and the second exhaust valve being located in the second exhaust port and defining a fifth diameter at least 30 percent of the first diameter.
 4. The engine assembly of claim 3, wherein the first intake port and the second intake port are located on a first radial half of the cylinder bore and the first exhaust port and the second exhaust port are located on a second radial half of the cylinder bore opposite the first radial half, a first line extending radially through a center of the cylinder bore and a center of the first intake valve extends at a first angle of between 40 degrees and 44 degrees relative to a line extending radially across the cylinder bore defining the first radial half and the second radial half when the first intake valve is in a seated position
 5. The engine assembly of claim 4, wherein a second line extending radially through the center of the cylinder bore and a center of the first exhaust valve extends at a second angle of between 39 degrees and 43 degrees relative to the line extending radially across the cylinder bore defining the first radial half and the second radial half when the first exhaust valve is in a seated position.
 6. The engine assembly of claim 2, wherein the third diameter is at least 32 percent of the first diameter.
 7. The engine assembly of claim 1, wherein the first intake valve extends at an angle of between 19 degrees and 21 degrees relative to a sidewall of the cylinder bore.
 8. The engine assembly of claim 1, wherein the second diameter is at least 37 percent of the first diameter.
 9. The engine assembly of claim 1, wherein the first diameter is less than 80 millimeters.
 10. The engine assembly of claim 1, wherein a first radial distance between a center of the cylinder bore and a radially innermost portion of the first intake valve is less than 25 millimeters when the first intake valve is in a seated position.
 11. An engine assembly comprising: an engine block defining a cylinder bore defining a first diameter less than 80 millimeters; a cylinder head coupled to the engine block and defining a first intake port and a first exhaust port in communication with the cylinder bore; a first intake valve located in the first intake port and defining a second diameter at least 35 percent of the first diameter; a first exhaust valve located in the first exhaust port and defining a third diameter at least 30 percent of the first diameter; a fuel injector in communication with the cylinder bore and located centrally relative to the cylinder bore; and a spark plug in communication with the cylinder bore and located centrally relative to the cylinder bore.
 12. The engine assembly of claim 11, further comprising a second intake valve and a second exhaust valve, the cylinder head defines a second intake port and a second exhaust port, the second intake valve being located in the second intake port and defining a fourth diameter at least 35 percent of the first diameter and the second exhaust valve being located in the second exhaust port and defining a fifth diameter at least 30 percent of the first diameter.
 13. The engine assembly of claim 12, wherein the first intake port and the second intake port are located on a first radial half of the cylinder bore and the first exhaust port and the second exhaust port are located on a second radial half of the cylinder bore opposite the first radial half, a first line extending radially through a center of the cylinder bore and a center of the first intake port extends at an angle of between 40 degrees and 44 degrees relative to a line extending radially across the cylinder bore defining the first radial half and the second radial half when the first intake valve is in a seated position.
 14. The engine assembly of claim 13, wherein a second line extending radially through the center of the cylinder bore and a center of the first exhaust port extends at an angle of between 39 degrees and 43 degrees relative to the line extending radially across the cylinder bore defining the first radial half and the second radial half when the first exhaust valve is in a seated position.
 15. The engine assembly of claim 11, wherein the first intake valve extends at an angle of between 19 degrees and 21 degrees relative to a sidewall of the cylinder bore and the first exhaust valve extends at an angle of between 17.5 degrees and 19.5 degrees relative to the sidewall of the cylinder bore.
 16. The engine assembly of claim 11, wherein the third diameter is at least 32 percent of the first diameter.
 17. The engine assembly of claim 16, wherein the second diameter is at least 37 percent of the first diameter.
 18. The engine assembly of claim 11, wherein the first diameter is less than 75 millimeters.
 19. An engine assembly comprising: an engine block defining a cylinder bore defining a first diameter less than 80 millimeters; a cylinder head coupled to the engine block and defining a first intake port, a second intake port, a first exhaust port, and a second exhaust port in communication with the cylinder bore, the first intake port and the second intake port being located on a first radial half of the cylinder bore and the first exhaust port and the second exhaust port being located on a second radial half of the cylinder bore opposite the first radial half; a first intake valve located in the first intake port and defining a second diameter at least 37 percent of the first diameter, a first line extending radially through a center of the cylinder bore and a center of the first intake valve extends at an angle of between 40 degrees and 44 degrees relative to a line extending radially across the cylinder bore defining the first radial half and the second radial half when the first intake valve is in a seated position; a first exhaust valve located in the first exhaust port and defining a third diameter at least 32 percent of the first diameter, a second line extending radially through the center of the cylinder bore and a center of the first exhaust valve extends at an angle of between 39 degrees and 43 degrees relative to the line extending radially across the cylinder bore defining the first radial half and the second radial half when the first exhaust valve is in a seated position; a second intake valve located in the second intake port and defining a fourth diameter at least 37 percent of the first diameter; a second exhaust valve located in the second exhaust port and defining a fifth diameter at least 32 percent of the first diameter; a fuel injector in communication with the cylinder bore and located centrally relative to the cylinder bore; and a spark plug in communication with the cylinder bore and located centrally relative to the cylinder bore.
 20. The engine assembly of claim 19, wherein the first diameter is less than 75 millimeters. 